Momcilovic v The Queen & Ors [2011] HCATrans 17

The High Court of Australia heard an appeal in *Momcilovic v The Queen & Ors*. The case concerned the constitutional validity of certain provisions of the *Drugs, Poisons and Controlled Substances Act 1981* (Vic) and the *Accident Compensation Act 1985* (Vic), specifically in relation to the presumption of possession of a drug found in a motor vehicle. The appellant, Mr. Momcilovic, had been convicted of possessing a drug after a quantity was found in his car, relying on a statutory presumption that he was in possession of the drug.

The central legal issue before the High Court was whether the statutory presumptions, which reversed the onus of proof onto the accused to demonstrate they did not possess the prohibited substance, were inconsistent with the implied constitutional prohibition against the legislative impairment of the judicial power of the Commonwealth. The Court was required to consider whether these presumptions, by requiring an accused to prove a negative, infringed upon the fundamental right to be presumed innocent until proven guilty, and whether such an infringement was constitutionally permissible.

A majority of the High Court held that the presumptions did not contravene the implied constitutional prohibition. The reasoning focused on the distinction between the legislative power to define criminal offences and the judicial power to determine guilt. The Court found that the presumptions did not usurp the function of the judiciary but rather defined the elements of the offence and the circumstances in which guilt could be established. The majority distinguished between presumptions that were conclusive and those that were rebuttable, with the latter being permissible as they allowed for the accused to present evidence to displace the presumption. The Court also considered the scope of the implied prohibition, noting it did not render all reversals of onus of proof unconstitutional.

The appeal was dismissed.